SMC-CBT1342165 R/O livestock ceramic bolus and SMC-CBT1322165 R/W livestock ceramic bolus are all make of Non-Lead and Non-Toxic materials. The whole production process confirms to ROHS standard .The encoding format of this production completely meet the standard of ISO11784/ISO11785. The unchangeable UID would be encoded in the production before it exwork. Especially use for cattle, sheep and deer, Inject ceramic bolus to animal's stomach, named cattle bolus. The difference is SMC-CBT1322165 R/W livestock ceramic bolus provides 256 Bit write area for customer to use.